One of the most common problems, with MAF Sensor equipped Ford (Mercury and Lincoln) vehicles, is that the MAF Sensor’s Hot Wires will get dirty (contaminated). This contamination will rob you of gas mileage and performance. Not only that, in some cases this condition will light up your Check Engine Light with a P0171 or P0174 (lean A/F mixture) Code. Well, this article will help you to clean your Mass Airflow Sensor in a step by step fashion. This article is broken up into several different parts and so to help you navigate it a little easier, here are its contents at a quick glance: Important Tips And Suggestions. Symptoms of a Dirty Ford MAF Sensor. Remove MAF Sensor. Clean MAF Sensor. No Improvement in Performance After MAF Clean. Important Suggestions and Tips Tip 1: The safest way to clean the MAF Sensor's Hot Wires, is to just spray them and let them air dry. Avoid physically touching them, like with a cotton swab, since this could break the Hot Wires. Tip 2: Do not use Carburetor Spray Cleaner or Brake Cleaner. Both of these are very harsh solvents and can damage the inner circuitry of the MAF Sensor and now you'll have a bad MAF Sensor on your hands (this I can vouch for from personal experience) Tip 3: Do not use gasoline. Gasoline will leave a petroleum residue on the Hot Wires and this residue will attract more dirt (like a magnet to metal), not to mention that gasoline is just too dangerous to use as a cleaner.